Pakistan has long maintained a tense and unstable relationship with its Afghan neighbour, the two countries divided since the emergence of Pakistan in 1947. The roots of the conflict between Afghanistan and Pakistan are, among other things, the result of the controversial legacy of British colonialism in the region. In the 19th century, Afghanistan became the toy of the « Great Game » between the Russian and British empires. When Russia began to take one Central Asian khanat at a time, the ever-expanding Tsarist empire began to move dangerously close to the Pamirs, the border country of England-India. In 1893, the British had to send Sir Mortimer Durand, a diplomat, to negotiate an agreement to demarcate the border between Afghanistan and British India. The new border, called the Durand Line, divided the Pashtun tribal areas into two parts. Half of the Pashtun tribal region was part of British India, the other half remained as part of Afghanistan. Since then, the border has been viewed with the utmost contempt and resentment by pashtuns on both sides of the line, which also results in Afghanistan losing the province of Balochistan and depriving the country of its historic access to the Arabian Sea. From the ridge of the Khwaja Amran Mountains, near the Psha Kotal Valley, which remains on British territory, the route will be traced in a direction that will leave Murgha Chaman and the Sharobo spring to Afghanistan, and will be halfway between the Fort of New Shaman and the Afghan outpost, known locally as Lashkar Dand.
The route will then be halfway between the station and the hill known as Mian Baldak and, when they turn south, they will return to the Khwaja Amran Mountains, leaving the Gwasha Post in the British territory and the Shorawak road west and south of Gwasha in Afghanistan. The British government will not prohibit interference in half a kilometre of the road. Pakistan`s Inter-Services Intelligence (ISI) secret service has been heavily involved in Afghanistan`s affairs since the late 1970s. During Operation Cyclone, the ISI, with the support and funding of the Central Intelligence Agency (CIA) in the United States, recruited mujahideen militant groups on the Pakistani side of the Durand Line to cross Afghan territory for missions to overthrow the Soviet-backed Afghan government.  Afghanistan Khad was one of two intelligence agencies allegedly bombing parts of the northwestern border (now Khyber Pakhtunkhwa) in the early 1980s.  The U.S. State Department has accused WAD (a KGB that created the Afghan secret service) of terrorist attacks in Pakistani cities in 1987 and 1988.  It is also accepted that the Afghan PDPA government supported the left-wing Organization Al-Zulfiqar of Pakistan, the group accused of hijacking a Pakistani International Airlines aircraft from Karachi to Kabul in 1981. Her Majesty`s Government in the United Kingdom has been a sad participant in the differences of opinion between the governments of Pakistan and Afghanistan on the status of the regions on the north-west border. Her Majesty`s Government considers Pakistan to be, in international law, the heir to the rights and duties of the former Government of India and Her Majesty`s Government in the United Kingdom in these territories and that the Durand Line is the international border.
 Pakistan inherited the 1893 Agreement and the 1919 Rawalpindi Treaty after the partition of British India in 1947. There has never been a formal agreement or ratification between Islamabad and Kabul.  Pakistan is of the view, and the International Convention on Legal Uti Possidetis supports the position that it should not require agreement on the border line;  The courts of several countries around the world and the Vienna Convention have generally confirmed by legal uti possidetis that binding bilateral agreements are « transmitted » to successor states.  Thus, a unilateral declaration by a party has no effect; Border changes must be done bilaterally.  The United States and other NATO countries often ignore this sensitive issue, probably because of the potential impact on their war strategy in Afghanistan.